Interference of dibutylphthalate on human prostate cell viability

Protective effects of black ginseng on testicular toxicity induced by Di-n-butyl phthalate in rats

Di-n-butyl phthalate (DBP) is a phthalate-based material used as a plasticizer to soften polyvinyl chloride, and classified as an endocrine disruptor with antiandrogen effects. Exposure to DBP induces oxidative stress in rat testes, resulting in testicular toxicity. Black ginseng (BG) exhibits a higher antioxidant activity than white or red ginseng following repeated heat treatment and processing. This study aimed to investigate whether the antioxidant activity of BG might protect against DBP-induced testicular toxicity in juvenile Sprague-Dawley rats. A significant decrease in testicular weight was observed in most groups treated with DBP alone or in combination with BG. However, a significant testicular weight increase was detected after exposure to BG (10 ml/kg) + DBP (500 mg/kg). The epididymal weight was significantly reduced with associated histological changes including irregular arrangement, atrophy of seminiferous tubules and Sertoli cells, and Leydig cell damage following exposure to DBP alone as well as BG (2.5 ml/kg) + DBP (500 mg/kg). However, no marked changes were observed in the shape of seminiferous tubules in control and BG + DBP groups. A significant decrease in serum testosterone levels was found after exposure to DBP, but no marked alterations in the BG + DBP groups. Protein expression levels of nuclear factor erythroid-derived 2-related factor (Nrf2), NAD(P)H dehydrogenase 1 (NQO1), and, heme oxygenase-1; (HO-1) were significantly higher following DBP treatment, but lowered in the BG + DBP groups. Evidence indicates that BG exerts a protective effect against DBP-induced testicular toxicity in rats.

Toxic effects of dibutyl phthalate on trophoblast through mitochondria mediated cellular dysfunction

Dibutyl phthalate is a chemical commonly used as a plasticizer in the production of daily necessaries, such as cosmetics and toys. Although several toxic effects of dibutyl phthalate have been confirmed, those related to pregnancy are unknown. Trophoblasts are critical for fetal and placental development, and trophoblast damage may cause preeclampsia. This study aimed to confirm the toxic effect of dibutyl phthalate on trophoblasts. We used the human trophoblast cell line HTR-8/SVneo and human choriocarcinoma JEG-3 cells as a placental trophoblast model to investigate the toxic effects of dibutyl phthalate. Both cell lines were treated with dibutyl phthalate (0-20 μg/mL) to verify the mechanisms regulating trophoblast function. Dibutyl phthalate treatment significantly reduced trophoblast viability, reduced invasion ability, and induced mitochondrial depolarization. Ultimately, dibutyl phthalate regulated the PI3K and MAPK signaling pathways and the expression of autophagy-related proteins ATG5, LC3B, and SQSTM1/p62. We concluded that dibutyl phthalate induced autophagy and effectively weakened trophoblast function. Additionally, we conducted experiments to assess the potential effects of monobutyl phthalate, a metabolite of dibutyl phthalate, on cellular mobility, penetration, and autophagy induction. Our results demonstrated that monobutyl phthalate impaired these functions and weakened the trophoblast barrier, after dibutyl phthalate metabolized. Thus, exposure to dibutyl phthalate and its metabolite monobutyl phthalate can damage trophoblast function, highlighting their potential as hazardous substances that impair trophoblast barrier integrity.

Risk assessment of China's Eastern Route of the South-to-north Water Diversion Project from the perspective of Phthalate Esters occurrence in the impounded lakes

Phthalate esters (PAEs) are widely utilized and can accumulate in lacustrine ecosystems, posing significant ecological and human health hazards. Most studies on PAEs focus on individual lakes, lacking a comprehensive and systematic perspective. In response, we have focused our investigation on characteristic lakes situated along the Eastern Route of the South-to-north Water Diversion Project (SNWDP-ER) in China. We have detected 16 PAE compounds in the impounded lakes of the SNWDP-ER by collecting surface water samples using solid-phase extraction followed by gas chromatography analysis. The concentration of PAEs were found to between 0.80 to 12.92 μg L-1. Among them, Bis (2-ethylhexyl) phthalate (DEHP) was the most prevalent, with mean concentration of 1.56 ± 0.62 μg L-1 (48.44%), followed by Diisobutyl phthalate (DIBP), 0.64 ± 1.40 μg L-1 (19.87%). Spatial distribution showed an increasing trend in the direction of water flow. Retention of DEHP and DIBP has led to increased environmental risks. DEHP, Dimethyl phthalate (DMP) etc. determined by agriculture and human activities. Additionally, Dibutyl phthalate (DBP) and DIBP mainly related to the use of agricultural products. To mitigate the PAEs risk, focusing on integrated management of the lakes, along with the implementation of stringent regulations to control the use of plasticizes in products.

Glyphosate Exposure Induces Cytotoxicity, Mitochondrial Dysfunction and Activation of ERα and ERβ Estrogen Receptors in Human Prostate PNT1A Cells

Glyphosate, the active ingredient of several broad-spectrum herbicides, is widely used throughout the world, although many adverse effects are known. Among these, it has been recognized as an endocrine disruptor. This work aimed to test the effects and potential endocrine disrupting action of glyphosate on PNT1A human prostate cells, an immortalized non-tumor epithelial cell line, possessing both ERα and ERβ estrogen receptors. The results showed that glyphosate induces cytotoxicity, mitochondrial dysfunction, and rapid activation of ERα and ERβ via nuclear translocation. Molecular analysis indicated a possible involvement of apoptosis in glyphosate-induced cytotoxicology. The apoptotic process could be attributed to alterations in mitochondrial metabolism; therefore, the main parameters of mitochondrial functionality were investigated using the Seahorse analyzer. Impaired mitochondrial function was observed in glyphosate-treated cells, with reductions in ATP production, spare respiratory capacity, and proton leakage, along with increased efficiency of mitochondrial coupling. Finally, the results of immunofluorescence analysis demonstrated that glyphosate acts as an estrogen disruptor determining the nuclear translocation of both ERs. Nuclear translocation occurred independent of dose, faster than the specific hormone, and persisted throughout treatment. In conclusion, the results collected show that in non-tumor prostate cells glyphosate can cause cell death and acts as a xenoestrogen, activating estrogen receptors. The consequent alteration of hormonal functions can have negative effects on the reproductive health of exposed animals, compromising their fertility.

Toxic Ingredients in Personal Care Products: A Dermatological Perspective

Environmental dermatology is the study of how environmental factors affect the integumentary system. The environment includes natural and built habitats, encompassing ambient exposure, occupational exposures, and lifestyle exposures secondary to dietary and personal care choices. This review explores common toxins found in personal care products and packaging, such as bisphenols, parabens, phthalates, per- and poly-fluoroalkyl substances, p-phenylenediamine, and formaldehyde. Exposure to these toxins has been associated with carcinogenic, obesogenic, or proinflammatory effects that can potentiate disease. In addition, these compounds have been implicated as endocrine-disrupting chemicals that can worsen dermatological conditions such as acne vulgaris, or dermatitis. Certain pollutants found in personal care products are not biodegradable and have the potential to bioaccumulate in humans. Therefore, even short-term exposure can cause long-lasting issues for communities. The skin is often the first point of contact for environmental exposures and serves as the conduit between environmental toxins and the human body. Therefore, it is important for dermatologists to understand common pollutants and their acute, subacute, and chronic impact on dermatological conditions to better diagnose and manage disease.

Implications on freshwater lake-river ecosystem protection suggested by organic micropollutant (OMP) priority list

Lake-river complex systems represent interconnected ecosystems wherein inflow rivers significantly influence the migration of terrigenous contaminants, particularly organic micropollutants (OMPs), into lakes. Given the extensive array of OMPs, screening for those with the highest potential hazard is crucial for safeguarding freshwater lake-river ecosystems. In this study, an optimized multi-criteria scoring method was applied to prioritize OMPs. Flux estimation was then performed to identify the contamination load contributed by the Le'an River to Poyang Lake. Higher concentrations of phthalate esters (PAEs) were detected in the lake-river system, ranging from 1154.5 to 22,732.8 ng/L, followed by antibiotics and polycyclic aromatic hydrocarbons (PAHs), while historical pollutant residues were comparably lower. Based on the prioritization methodology, 27 compounds, encompassing eight PAEs, six organochlorine pesticides (OCPs), six polychlorinated biphenyls (PCBs), five PAHs and two antibiotics, emerged as priority pollutants. Multiple risk assessments revealed that priority PAEs posed relatively high ecological and human health risks; concurrently, the annual fluxes of individual priority PAEs into the lake all exceeded 1000 kg, with DBP, DEHP and BBP fluxes reaching 18,352, 10,429, and 7825 kg, respectively. This research offers valuable insights stemming from OMP prioritization to aid in the conservation of freshwater lake ecosystems, particularly concerning lake-river system integrity.

Integrated transcriptome and proteome analysis indicates potential biomarkers of prostate cancer in offspring of pregnant rats exposed to a phthalate mixture during gestation and lactation

As the second leading cause of death for cancer among men worldwide, prostate cancer (PCa) prevention and detection remain a critical challenge. One aspect of PCa research is the identification of common environmental agents that may increase the risk of initiation and progression of PCa. Endocrine disrupting chemicals (EDCs) are strong candidates for risk factors, partially because they alter essential pathways for prostate gland development and oncogenesis. Phthalates correspond to a set of commercially used plasticizers that humans are exposed to ubiquitously. Here, we show that maternal exposure to a phthalate mixture interferes with the expression profile of mRNA and proteins in the ventral prostate of offspring and increases the susceptibility to prostate adenocarcinomas in aged animals. The data highlight Ubxn11, Aldoc, Kif5c, Tubb4a, Tubb3, Tubb2, Rab6b and Rab3b as differentially expressed targets in young and adult offspring descendants (PND22 and PND120). These phthalate-induced targets were enriched for pathways such as: dysregulation in post-translational protein modification (PTPM), cell homeostasis, HSP90 chaperone activity, gap junctions, and kinases. In addition, the Kif5c, Tubb3, Tubb2b and Tubb4a targets were enriched for impairment in cell cycle and GTPase activity. Furthermore, these targets showed strong relationships with 12 transcriptional factors (TF), which regulate the phosphorylation of eight protein kinases. The correlation of TF-kinases is associated with alterations in immune system, RAS/ErbB/VEGF/estrogen/HIF-1 signaling pathways, cellular senescence, cell cycle, autophagy, and apoptosis. Downregulation of KIF5C, TUBB3 and RAB6B targets is associated with poor prognosis in patients diagnosed with adenocarcinoma. Collectively, this integrative investigation establishes the post-transcriptional mechanisms in the prostate that are modulated by maternal exposure to phthalate mixture during gestation and lactation.

Effects of Dibutylphthalate and Steroid Hormone Mixture on Human Prostate Cells

Phthalates are a family of aromatic chemical compounds mainly used as plasticizers. Among phthalates, di-n-butyl phthalate (DBP) is a low-molecular-weight phthalate used as a component of many cosmetic products, such as nail polish, and other perfumed personal care products. DBP has toxic effects on reproductive health, inducing testicular damage and developmental malformations. Inside the male reproductive system, the prostate gland reacts to both male and female sex steroids. For this reason, it represents an important target of endocrine-disrupting chemicals (EDCs), compounds that are able to affect the estrogen and androgen signaling pathways, thus interfering with prostate homeostasis and inducing several prostate pathologies. The aim of this project was to investigate the effects of DBP, alone and in combination with testosterone (T), 17β-estradiol (E2), and both, on the normal PNT1A human prostate cell-derived cell line, to mimic environmental contamination. We showed that DBP and all of the tested mixtures increase cell viability through activation of both estrogen receptor α (ERα) and androgen receptor (AR). DBP modulated steroid receptor levels in a nonmonotonic way, and differently to endogenous hormones. In addition, DBP translocated ERα to the nucleus over different durations and for a more prolonged time than E2, altering the normal responsiveness of prostate cells. However, DBP alone seemed not to influence AR localization, but AR was continuously and persistently activated when DBP was used in combination. Our results show that DBP alone, and in mixture, alters redox homeostasis in prostate cells, leading to a greater increase in cell oxidative susceptibility. In addition, we also demonstrate that DBP increases the migratory potential of PNT1A cells. In conclusion, our findings demonstrate that DBP, alone and in mixtures with endogenous steroid hormones, acts as an EDC, resulting in an altered prostate cell physiology and making these cells more prone to cancer transformation.

Impacts of heavy metal exposure on the prostate of murine models: Mechanisms of toxicity

Heavy metals are elements found into the environment mainly due to anthropogenic activities. Naturally occurring and higher released doses cause disorders in the prostate, which depends on appropriate hormonal regulation, and exposure to heavy metals may impair prostate homeostasis. The current work highlighted the main mechanisms of toxicity of different environmental heavy metal contaminants, such as aluminum, arsenic, cadmium, chromium, lead, mercury, and nickel, and their impacts found in the prostate morphophysiology of murine models. The repercussions triggered by heavy metals on the prostate include hormonal imbalance and oxidative damage, leading to morphological alterations, which can vary according to the chemical properties of each element, exposure time and concentration, and age. The information of altered biological pathways and its impacts on the prostate of exposed murines are related to human outcomes being useful in the real context of human exposure.

Combined Toxicities of Di-Butyl Phthalate and Polyethylene Terephthalate to Zebrafish Embryos

The increasing concern for the ecological risks of microplastics (MPs) as carriers of hydrophobic organic contaminants is evident. Di-butyl phthalate (DBP) is extensively utilized as an additive in plastic products, and both DBP and MPs are widespread in the environment. However, the combined toxicity of these substances remains uncertain. In this study, zebrafish embryos were employed to assess the toxic effects of polyethylene terephthalate (PET, MPs) and DBP, with a focus on the DBP toxicities influenced by PET. The embryonic chorion was partially covered by PET particles, and PET led to a delayed hatching of zebrafish embryos without inducing death or teratogenesis. On the other hand, exposure to DBP considerably inhibited the hatching of embryos, leading to severe lethal and teratogenic effects. The most common phenotypes induced by DBP exposure were delayed yolk sac absorption and pericardial edema. The mortality increased in co-treatment with 100 particles/mL PET and 2 mg/L DBP at 24 hpf and 48 hpf. The malformation phenotype, bent notochord, and delayed yolk sac absorption became more severe in 1 mg/L DBP exposition with the co-exposure of 100 particles/mL PET at 72 hpf. PET might act as a carrier that enhances the bioavailability of ambient DBP.

Investigation of the Biosafety of Antibacterial Mg(OH)2 Nanoparticles to a Normal Biological System

The toxicity of Mg(OH)₂ nanoparticles (NPs) as antibacterial agents to a normal biological system is unclear, so it is necessary to evaluate their potential toxic effect for safe use. In this work, the administration of these antibacterial agents did not induce pulmonary interstitial fibrosis as no significant effect on the proliferation of HELF cells was observed in vitro. Additionally, Mg(OH)₂ NPs caused no inhibition of the proliferation of PC-12 cells, indicating that the brain's nervous system was not affected by Mg(OH)₂ NPs. The acute oral toxicity test showed that the Mg(OH)₂ NPs at 10,000 mg/kg induced no mortality during the administration period, and there was little toxicity in vital organs according to a histological analysis. In addition, the in vivo acute eye irritation test results showed little acute irritation of the eye caused by Mg(OH)₂ NPs. Thus, Mg(OH)₂ NPs exhibited great biosafety to a normal biological system, which was critical for human health and environmental protection.

DBP induced autophagy and necrotic apoptosis in HepG2 cells via the mitochondrial damage pathway

Phthalate esters (PAEs) are widely present in human tissues and pose significant health risks. In this study, HepG2 cells were treated with 0.0625, 0.125, 0.25, 0.5 and 1 mM Dibutyl phthalate (DBP) for 48 h to investigate mitochondrial toxicity. The results showed that DBP caused mitochondrial damage, autophagy, apoptosis and necroptosis; Transcriptomics analysis identified that MAPK and PI3K were significant factors in the cytotoxic changes induced by DBP; N-Acetyl-L-cysteine (NAC), SIRT1 activator, ERK inhibitor, p38 inhibitor and ERK siRNA treatments counteracted the changes of SIRT1/PGC-1α and Nrf2 pathway-related proteins, autophagy and necroptotic apoptosis proteins induced by DBP. While PI3K and Nrf2 inhibitors exacerbated the changes in SIRT1/PGC-1α, Nrf2-associated proteins and autophagy and necroptosis proteins induced by DBP. In addition, the autophagy inhibitor 3-MA alleviated the increase in DBP-induced necroptosis proteins. These results suggested that DBP-induced oxidative stress activated the MAPK pathway, inhibited the PI3K pathway, which in turn inhibited the SIRT1/PGC-1α pathway and Nrf2 pathway, thereby causing cell autophagy and necroptosis.

In silico, in vitro and in vivo studies: Dibutyl phthalate promotes prostate cancer cell proliferation by activating Forkhead Box M1 and remission after Natura-α pretreatment

Dibutyl phthalate (DBP) is widely used in perfumes, cosmetics, shampoos and medical devices. It is ubiquitous in the environment and greatly endangers people's health. Several studies have reported that being exposed to it can promote the development of lung cancer, breast cancer, hepatoma, and multiple myeloma. However, there are still few studies on the specific molecular mechanism and prevention methods of DBP promoting the progression of prostate cancer. This study, in silico, in vitro and in vivo, aims to explore the promoting effect of DBP on prostate cancer cell proliferation. In silico analysis, we obtained a set of DBP interactive genes by utilizing TCGA, CTD and GEO database. These genes are mainly enriched in cell cycle regulatory pathways and they have high degree of homogeneity. We found that these genes shared one transcription factor - Forkhead Box M1 (FOXM1) by performing Chip-X Enrichment Analysis (Version 3.0). FOXM1, once called the 2010 Molecule of the Year, aberrantly expressed in up to 20 kinds of tumors. In vitro experiments, we used DBP at concentrations of 10^-8 M and 5 * 10^-7 M to treat C4-2 and PC3 cells for 6 days, respectively. Cell viability was promoted significantly. When Natura-α was added in the background of above-mentioned concentration of DBP, this effect was significantly inhibited. In addition, we also found that DBP can interfering with the efficacy of enzalutamide therapy. The introduction of Natura-α can also reverse this phenomenon. In vivo, subcutaneous tumor formation experiments in nude mice, 800 mg/kg/day DBP can promote the growth of prostate cancer. This phenomenon was suppressed when Natura-α (100 mg/kg/day) was added. Based on the results of the above three levels, we confirmed that DBP can target FOXM1 to promote prostate cancer cell proliferation. Natura-α can reverse its cancer-promoting effect. This study provides new insights into the impact of DBP on prostate cancer.

Quercetin ameliorates Di (2-ethylhexyl) phthalate-induced nephrotoxicity by inhibiting NF-κB signaling pathway

This study aimed to evaluate the possible protective effects of quercetin, a natural flavonoid, against nephrotoxicity induced by Di (2-ethylhexyl) phthalate (DEHP) in kidney tissue of rats and human embryonic kidney (HEK) 293 cell line. The HEK-293 cells were treated with different concentrations of quercetin 24 h before treatment with monoethylhexyl phthalate (MEHP). Male rats were treated with 200-mg/kg DEHP, 200-mg/kg DEHP plus quercetin (50 and 100 mg/kg), and 200-mg/kg DEHP plus vitamin E (20 mg/kg) for 45 days by gavage. Quercetin treatment reduced cytotoxicity and oxidative damage inducing by MEHP in HEK-293 cells. The in vivo findings showed that 100-mg/kg quercetin significantly suppressed DEHP-induced kidney damage. For exploring the involved mechanisms, the expressions of nuclear factor E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), nuclear factor kappa B (NFκB), and tumor necrosis factor alpha (TNFα) genes were determined via real-time Polymerase chain reaction (PCR) assay. High dose of quercetin significantly decreased the gene expressions of NF-κB and TNFα, whereas the alternations of Nrf2 and HO-1 gene expressions were not significant in quercetin groups in compared with DEHP group. These findings suggested that the suppression of DEHP-induced nephrotoxicity via quercetin is correlated, at least in part, with its potential to regulate NF-κB signaling pathway.

Impacts of endocrine-disrupting chemicals on prostate function and cancer

Because of their historical mode of action, endocrine-disrupting chemicals (EDCs) are associated with sex-steroid receptors, namely the two estrogen receptors (ERα and ERβ) and the androgen receptor (AR). Broadly, EDCs can modulate sex-steroid receptor functions. They can also indirectly impact the androgen and estrogen pathways by influencing steroidogenesis, expression of AR or ERs, and their respective activity as transcription factors. Additionally, many of these chemicals have multiple cellular targets other than sex-steroid receptors, which results in a myriad of potential effects in humans. The current article reviews the association between prostate cancer and the endocrine-disrupting functions of four prominent EDC families: bisphenols, phthalates, phytoestrogens, and mycoestrogens. Results from both in vitro and in vivo models are included and discussed to better assess the molecular mechanisms by which EDCs can modify prostate biology. To overcome the heterogeneity of results published, we established common guidelines to properly study EDCs in the context of endocrine diseases. Firstly, the expression of sex-steroid receptors in the models used must be determined before testing. Then, in parallel to EDCs, pharmacological compounds acting as positive (agonists) and negative controls (antagonists) have to be employed. Finally, EDCs need to be used in a precise range of concentrations to modulate sex-steroid receptors and avoid off-target effects. By adequately integrating molecular endocrinology aspects in EDC studies and identifying their underlying molecular mechanisms, we will truly understand their impact on prostate cancer and distinguish those that favor the progression of the disease from those that slow down tumor development.

Endocrine Disruptors and Prostate Cancer

The role of endocrine disruptors (EDs) in the human prostate gland is an overlooked issue even though the prostate is essential for male fertility. From experimental models, it is known that EDs can influence several molecular mechanisms involved in prostate homeostasis and diseases, including prostate cancer (PCa), one of the most common cancers in the male, whose onset and progression is characterized by the deregulation of several cellular pathways including androgen receptor (AR) signaling. The prostate gland essentiality relies on its function to produce and secrete the prostatic fluid, a component of the seminal fluid, needed to keep alive and functional sperms upon ejaculation. In physiological condition, in the prostate epithelium the more-active androgen, the 5α-dihydrotestosterone (DHT), formed from testosterone (T) by the 5α-reductase enzyme (SRD5A), binds to AR and, upon homodimerization and nuclear translocation, recognizes the promoter of target genes modulating them. In pathological conditions, AR mutations and/or less specific AR binding by ligands modulate differently targeted genes leading to an altered regulation of cell proliferation and triggering PCa onset and development. EDs acting on the AR-dependent signaling within the prostate gland can contribute to the PCa onset and to exacerbating its development.

Distribution and characteristics of microplastics and phthalate esters from a freshwater lake system in Lesser Himalayas

The occurrence, distribution, characterization and quantification of microplastics (MPs) and phthalic acid esters (PAEs) from the freshwater aquatic environment are not thoroughly explored in the Indian Himalayas despite concern over their adverse effects on human health and ecosystem. In this study, we have investigated the presence of MPs and PAEs in an aquatic system from Indian subcontinent. The MPs were detected in all water and sediment samples with abundances ranging from 02-64 particles/L and 15-632 particles/kg dw, respectively. The abundance of MPs, dominated by polyethylene and polystyrene, with the majority being fibres and fragments indicated that they were derived from plastic paints, boats or synthetic products. The concentrations of PAEs in the surface sediment samples varied from 06-357 ng/g dw. The most abundant PAEs in the sediments were dibutyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP), since they were present in all the samples collected from the lake basin. The relatively higher abundances of MPs and higher concentrations of PAEs were generally found in the vicinity of areas impacted by anthropogenic activities. A clear correlation between the abundance of microplastics and PAEs concentration was observed suggesting that they are closely attributed to a single source. This study also provides an alternative approach to utilize the chemical additives in plastics as markers to trace the presence and distribution of MPs in the aquatic environment.

Combined Effects of Different Endocrine-Disrupting Chemicals (EDCs) on Prostate Gland

Endocrine-disrupting chemicals (EDCs) belong to a heterogeneous class of environmental pollutants widely diffused in different aquatic and terrestrial habitats. This implies that humans and animals are continuously exposed to EDCs from different matrices and sources. Moreover, pollution derived from anthropic and industrial activities leads to combined exposure to substances with multiple mechanisms of action on the endocrine system and correlated cell and tissue targets. For this reason, specific organs, such as the prostate gland, which physiologically are under the control of hormones like androgens and estrogens, are particularly sensitive to EDC stimulation. It is now well known that an imbalance in hormonal regulation can cause the onset of various prostate diseases, from benign prostate hyperplasia to prostate cancer. In this review, starting with the description of normal prostate gland anatomy and embryology, we summarize recent studies reporting on how the multiple and simultaneous exposure to estrogenic and anti-androgenic compounds belonging to EDCs are responsible for an increase in prostate disease incidence in the human population.

An approach to classifying occupational exposures to endocrine disrupting chemicals by sex hormone function using an expert judgment process

Endocrine disrupting chemicals (EDCs) are exogenous substances that interfere with the endocrine system and cause adverse effects. We aimed to classify the effects of 24 known EDCs, prevalent in certain occupations, according to four modes of action (estrogenic, antiestrogenic, androgenic, and/or antiandrogenic). A literature search, stratified into four types of literature was conducted (namely: national and international agency reports; review articles; primary studies; ToxCast^TM). The state of the evidence of each EDC on sex hormone function was summarized and reviewed by an expert panel. For each mode of action, the experts evaluated the likelihood of endocrine disruption in five categories: "No", "Unlikely", "Possibly", "Probably", and "Yes". Seven agents were categorized as "Yes," or having strong evidence for their effects on sex hormone function (antiandrogenic: lead, arsenic, butylbenzyl phthalate, dibutyl phthalate, dicyclohexyl phthalate; estrogenic: nonylphenol, bisphenol A). Nine agents were categorized as "Probable," or having probable evidence (antiandrogenic: bis(2-ethylhexyl)phthalate, nonylphenol, toluene, bisphenol A, diisononyl phthalate; androgenic: cadmium; estrogenic: copper, cadmium and; anti-estrogenic: lead). Two agents (arsenic, polychlorinated biphenyls) had opposing conclusions supporting both "probably" estrogenic and antiestrogenic effects. This synthesis will allow researchers to evaluate the health effects of selected EDCs with an added level of precision related to the mode of action.

Mechanistic insight into toxicity of phthalates, the involved receptors, and the role of Nrf2, NF-κB, and PI3K/AKT signaling pathways

The wide use of phthalates, as phthalates are used in the manufacturing of not only plastics but also many others goods, has become a main concern in the current century because of their potency to induce deleterious effects on organism health. The toxic effects of phthalates such as reproductive toxicity, cardiotoxicity, hepatotoxicity, nephrotoxicity, teratogenicity, and tumor development have been widely indicated by previous experimental studies. Some of the important mechanisms of toxicity by phthalates are the induction and promotion of inflammation, oxidative stress, and apoptosis. Awareness of the involved molecular pathways of these mechanisms will permit the detection of exact molecular targets of phthalates to protect or treat their toxicity. Up to now, various transcription factors and signaling pathways have been associated with phthalate-induced toxicity which by influencing on nuclear surface and the expression of different genes can alter cell hemostasis. In different studies, the role of nuclear factor erythroid 2-related factor 2 (Nrf2), nuclear factor-κB (NF-κB), and phosphatidylinositol-3-kinase (PI3K)/AKT signaling pathways in processes of oxidative stress, inflammation, apoptosis, and cancer has been shown following exposure to phthalates. In the present review, we aim to survey experimental studies (in vitro and in vivo) in order to show firstly the most involved receptors and also the importance and the role of the mentioned signaling pathways in phthalate-induced toxicity, and with considering this point, the future studies can focus on these molecular targets as a strategic method to reduce environmental chemicals-induced toxicity especially phthalates toxic effects.

Emerging endocrine disruptors in two edible fish from the Persian Gulf: Occurrence, congener profile, and human health risk assessment

The occurrence of endocrine disrupting chemicals (EDCs) has been determined in two widely consumed fish species from Persian Gulf i.e., Epinephelus coioides and Platycephalus indicus by applying a validated analytical for the simultaneous detection of fourteen EDCs. The concentrations of all detected EDCs were greater in the liver than in the muscle (except for bisphenol A in P. indicus), suggesting a prolonged exposure of the fishes to these pollutants in the Persian Gulf. Specifically, the results showed that di (2-ethylhexyl) phthalate (DEHP) was the compound detected most frequently and at the highest concentration in both species. DEHP levels in ranged from 6.68 to 297.48 μg g-dw^-1 and from 13.32 to 350.52 μg g-dw^-1, in muscle and in liver, respectively. A risk assessment study was conducted, and demonstrated that consuming two fish based- meals per week may result in a moderate risk especially for vulnerable population groups.

Exposure to Di-2-ethylhexyl Phthalate and Benign Prostatic Hyperplasia, NHANES 2001-2008

30% of men suffer from benign prostatic hyperplasia (BPH) worldwide. As one of the most important members of Phthalate esters, previous studies suggested ubiquitous Di-(2-ethylhexyl) phthalate (DEHP) exposure is associated with such male disorders by interfering with endocrine system, however, little is known about the association between DEHP exposure and BPH. The objective of this study was to study the potential association by the 2001-2008 National Health and Nutrition Examination Survey (NHANES) data. The data was collected, and multiple logistic regression was adapted to measure the association. The concentrations of DEHP (∑DEHP) were calculated by each metabolite and split into quartiles for analysis. Results showed that the odds ratio (OR) decreased with increased ∑DEHP concentration. In the crude model, the OR for the second quartile (OR = 1.60, 95%CI [1.24, 2.07]) was obviously higher compared with the lowest quartile. However, the OR for the highest quartile (OR = 0.55, 95%CI [0.44,0.69]) was lower than that for the third quartile (OR = 0.77, 95%CI [0.61, 0.97]), and the OR for the third and the highest quartile were significantly lower than that of the lowest quartile, which suggested biphasic effects of DEHP based on concentration. The results showed the same trend after adjusting confounding factors. The study suggested that the DEHP exposure is associated with DEHP, and the results adds limited evidence to study this topic, however, further researches are needed to determine if the status of BPH can be changed by controlling DEHP exposure.

Dibutyl phthalate induces allergic airway inflammation in rats via inhibition of the Nrf2/TSLP/JAK1 pathway

Dibutyl phthalate (DBP), an important plastic contaminant in the environment, is known to cause organ toxicity. Although current research has shown that DBP-induced organ toxicity is associated with oxidative stress, the toxic effect of DBP on the lungs have not been fully elucidated. Therefore, we investigated the potential mechanism by which DBP induces pulmonary toxicity using a model of DBP-induced allergic airway inflammation in rats. The results showed that chronic exposure to DBP induced histopathological damage, inflammation, oxidative stress, apoptosis, and increased the protein levels of thymic stromal lymphopoietin (TSLP) and its downstream protein Janus kinase 1 (JAK1) and signal transducer and activator of transcription 6 (STAT6). Moreover, DBP exposure inhibited nuclear factor-erythroid-2-related factor 2 (Nrf2) and levels of its target genes NAD(P)H quinone oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1). Additionally, using in vitro experiments, we found that DBP induced oxidative stress, reduced cell viability, and inhibited the Nrf2/HO-1/NQO1 pathway in mouse alveolar type II epithelial cell line. Overall, these data demonstrate that DBP induces allergic airway inflammation in rats via inhibition of the Nrf2/TSLP/JAK1 pathway.

Adrenal gland response to endocrine disrupting chemicals in fishes, amphibians and reptiles: A comparative overview

The adrenal gland is an essential component of the body stress response; it is formed by two portions: a steroidogenic and a chromaffin tissue. Despite the anatomy of adrenal gland is different among classes of vertebrates, the hormones produced are almost the same. During stress, these hormones contribute to body homeostasis and maintenance of ion balance. The adrenal gland is very sensitive to toxic compounds, many of which behave like endocrine-disruptor chemicals (EDCs). They contribute to alter the endocrine system in wildlife and humans and are considered as possible responsible of the decline of several vertebrate ectotherms. Considering that EDCs regularly can be found in all environmental matrices, the aim of this review is to collect information about the impact of these chemical compounds on the adrenal gland of fishes, amphibians and reptiles. In particular, this review shows the different behavior of these "sentinel species" when they are exposed to stress condition. The data supplied in this review can help to further elucidate the role of EDCs and their harmful impact on the survival of these vertebrates.

Impacts of anthropogenic activities on spatial variations of phthalate esters in water and suspended particulate matter from China's lakes

In the largest developing country, China, plastic has become a serious environmental issue because of its overuse and non-treatment. In fact, plasticizers, such as phthalate esters (PAEs), are more toxic than plastic, and their global awareness is rising. To determine the response of sensitive PAE congeners to the anthropogenic activities in a typical lake ecosystem of China, in the present study, 12 PAEs in the water and the suspended particulate matter (SPM) phases of 46 lakes in China were measured. The concentrations of all the Σ₁₂ PAEs in water and SPM phases ranged from 3.647 to 65.618 μg/L and 0.175 to 10.921 μg/L, respectively. Di-n-butyl phthalate (DnBP) was the predominant PAEs in the water phase, whereas diisobutyl phthalate (DIBP), DnBP, and bis(2-ethylhexyl) phthalate (DEHP) were the dominating PAEs in the SPM phase. Forty-six lakes were divided into four groups based on the anthropogenic activity intensities. The PAEs in both the water and SPM phases had increasing tendency along the human activity gradient. DIBP appears to be a sensitive PAE indicator that could distinguish the lake regions with different human industrial and agricultural activities. Dimethyl phthalate (DMP) and diethyl phthalate (DEP) are intensely affected by industrial development. DnBP and DEHP were positively correlated with agricultural activities, including the use of films and pesticides. It is suggested to control the addition and usage of PAEs in agricultural activities and improve their removal rates in industrial wastewater to reduce the PAE pollution in the water bodies in the environment management of China.

Intrauterine exposure to diethylhexyl phthalate disrupts gap junctions in the fetal rat testis

Fetal exposure to certain phthalate esters can disrupt testis development in rodents and lead to male reproductive disorders, but with a causal link less certain in humans. Di(2-ethylhexyl) phthalate (DEHP) is one of the most common phthalates found in the environment and in rodents it is known to induce serious testis toxicity, as well as male reproductive disorders including cryptorchidism, hypospadias, impaired spermatogenesis and reduced fertility. In this study, we show that perinatal DEHP exposure disrupts gap junction localization in fetal and postnatal rat testis and correlate these findings to morphological changes. The protein Connexin 43 (CX43), normally expressed strongly in testicular gap junctions, was markedly downregulated in Leydig cells of DEHP-exposed fetal testes. In the postnatal testes, CX43 expression was recovered in the DEHP-exposed animals, even though Leydig cell clusters and malformed cords with intratubular Leydig cells were still present.

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DEHP disrupts gap junction localization in fetal and postnatal rat testis.

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DEHP exposure reduces Cx43-positive gap junctions in Leydig cell clusters in fetal rat testis.

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Leydig cell gap junctions recover in postnatal testis after early life DEHP exposure.

Nonylphenol acts on prostate adenocarcinoma cells via estrogen molecular pathways

Estrogens play a role in the patho-physiology of the prostate. In the present work we studied the effects of nonylphenol (NP), a xenoestrogen, on human adenocarcinoma prostate cells (LNCaP). In order to understand molecular and cellular involvement, we observed the effects on cell cycle and we investigated the expression and the cellular localization of estrogen receptors and gene expression of cyclin D1, ki-67, c-myc, IL-8, IL-1β. We performed the same experiments with 17β-estradiol (E2), the most abundant estrogen circulating in nonpregnant humans in order to compare these two different substances. We demonstrated the ability of 1 × 10^-10 M NP to induce proliferation of LNCaP, S-phase progression, increase of ERα expression and its translocation from the cytoplasm to the nucleus. Moreover, we observed an up-regulation of key target genes involved in cell cycle and inflammation process. Particularly, after NP treatment, IL-8 and IL-1β mRNA levels are increased more than 50% indicating a major NP involvement in inflammation processes than E2. These data suggest the proliferative effects of NP on prostate adenocarcinoma cells and highlight some aspects of molecular pathways involved in prostate responses to NP.

The expression of estrogen receptors during the Mytilus galloprovincialis ovarian cycle

The aim of this paper is to assess, by real-time polymerase chain reaction and in situ hybridization, the expression of estrogen receptors ER1 and ER2 during the ovarian cycle of Mytilus galloprovincialis. By considering four phases of the reproductive cycle, that is stasis and previtellogenic stage (Stage 0), early vitellogenesis (Stage I), vitellogenesis (Stage II), full-grown oocyte (Stage III), our investigation demonstrates that the two receptors are differently expressed during the phases investigated of the ovarian cycle: ER1 reaches the highest level at Stage III, whereas ER2 reaches the highest level at Stage II, with ER2 always present at higher levels than ER1. The stage-dependent receptor expression was recorded within oocytes, follicle cells, and adipogranular cells. No ER1 and ER2 messenger RNAs (mRNAs) were found within vesicular cells. It is to be noted that the ER1 and ER2 expression within the growing oocytes, the follicular, and adipogranular cells overlaps with that of the mRNA for vitellogenin in the same cells, strongly suggesting that in Mytilus, as in vertebrates studied so far, the vitellogenin expression is under the control of estrogens.

Sex hormones and oxidative stress mediated phthalate-induced effects in prostatic enlargement

Prostatic enlargement might affect up to 30% of men and can cause signs and symptoms in the lower urinary tract in the elderly. Imbalanced estrogen and androgen secretions are important in prostatic physiopathology. Phthalates-environmental endocrine disruptors-affect androgen secretion and disrupt sexual organs, including testes and the prostate, but the underlying mechanisms are unclear. Using European Association of Urology (EAU) guidelines, we recruited from urology clinics in southern Taiwan 207 elderly men diagnosed with benign prostatic hyperplasia (BPH) and prostatic enlargement between 2015 and 2017. We took blood and urine samples from all patients on the same day. We used multivariate linear regression, associations, and potential interactions after we had measured and analyzed oxidative stress (OS) markers, steroidal hormones, and 11 urinary phthalate metabolites, and then we adjusted for confounders. Di(2-ethylhexyl) phthalate (DEHP) metabolite levels, particularly urinary mono-(2-ethylhexyl) phthalate, were positively associated with androgen, estrogen, hormone ratios, inducible nitric oxide synthetase (iNOS), 8-hydroxy-2'-deoxyguanosine (8-OHdG), prostate specific antigen (PSA), and prostate volume (PV) (p < 0.05). PV and PSA were positively associated with androgen, estrogen, hormone ratios and OS markers (p < 0.05). The estimated percentages of exposure to phthalates in prostatic enlargement mediated by androgen, estrogen, and OS markers ranged from 3.5% to 63.1%. Exposure to DEHP promoted the progress of BPH by increasing dihydrotestosterone (DHT), estradiol (E₂), the converted enzymes aromatase and 5α reductase, and reactive oxygen species (ROS) (8-OHdG and iNOS) production. Sex hormones and OS might be important hyperplasia-promoters after a patient has been exposed to phthalates, especially to DEHP.

Androgenic/antiandrogenic activities of PAEs determined by a novel AR-mediated reporter gene assay based on LLC-MK2 cells

Recent reports have concentrated on some androgens/antiandrogens and confirmed that certain chemicals have demonstrated androgenic/antiandrogenic activities in vitro. However, it is still unknown whether more chemicals in the human environment possess endocrine toxicity. 58A novel AR-mediated reporter gene assay based on LLC-MK2 cells was established by transiently co-transfecting with pARE-sv40-Luc, hAR-pcDNA3.1 and pRL-tk. pARE-sv40-Luc was constructed using a pGL3-promoter plasmid with three repeated androgen responsive elements. hAR-pcDNA3.1 was constructed using pcDNA3.1 with a hAR sequence. After transfection for 12 h, the culture medium was exposed to various concentrations of dihydrotestosterone (DHT) and other test chemicals (phthalic acid esters and dexamethasone) in order to measure the androgenic/antiandrogenic activity. The assay possessed a concentration-dependent response to DHT from 10^-12 M to 10^-6 M. Nilutamide concentrations of over 10^-7 M completely blocked the luciferase expression induced by 10^-9 M DHT. Other data showed that DBP, DEHP and MEHP possessed weak androgenic activity for certain concentration ranges, while DMP, DINP and DIBP did not show any androgenic activity. Moreover, five PAEs (DBP, DEHP, DINP, DIBP and MEHP) showed corresponding antiandrogenic activities for certain concentrations with an approximate tendency (MEHP > DBP > DEHP > DIBP > DINP). The assay is high-throughput, specific, and sensitive for the detection of androgenic/antiandrogenic chemicals. In addition, PAEs (especially transitional PAEs) exhibited corresponding androgenic/antiandrogenic activities for certain concentration ranges.

Exposure to DBP induces the toxicity in early development and adverse effects on cardiac development in zebrafish (Danio rerio)

Dibutyl phthalate (DBP) is one of the most ubiquitous plasticizers used worldwide and has been frequently detected in soil, water, atmosphere, and other environmental media. DBP has become a ubiquitous environment contaminant and causes serious pollution. However, much attention has been paid to the toxicity of DBP, with only limited attention paid to its detrimental effects on the heart. In the present study, we investigated the toxicity of DBP in zebrafish embryo development, especially adverse effects on cardiac development. Embryos at 4-h post-fertilization (hpf) were exposed to different concentrations of DBP (0, 0.36, 1.8 and 3.6 μM) until 72 hpf. Exposure to DBP resulted in morphological abnormalities in zebrafish embryos. Exposure to 1.8 μM DBP significantly affected the growth, malformation rate, cardiac malformation rate and cardiac looping. Exposure to 3.6 μM DBP significantly affected all endpoints. To preliminarily understand the underlying mechanisms of toxic effects of DBP on the embryo heart, we examined the expression of master cardiac transcription factors such as NKX2.5 and TBX5. The expression of this two transcription factors was significantly reduced with DBP treatment in a dose-dependent manner. Our results demonstrate that exposure to DBP resulted in zebrafish developmental toxicity, pericardial edema, cardiac structure deformities and function alteration, and changed the expression of master cardiac transcription factors such as NKX2.5 and TBX5.